For the first time, researchers have visually tracked the timing and location of fat accumulation within intact fruit fly cells in high resolution.
The new optical imaging tool developed by bioengineering Professor Lingyan Shi's lab at the University of California San Diego is already being used to untangle the often discussed, yet mysterious, links between diet and things like obesity, diabetes, and aging.
The research was published in the journal Aging Cell by bioengineers at the UC San Diego Jacobs School of Engineering.
Fruit fly's storage of fats
FREDRIK VON ERICHSEN/DPA/AFP via Getty Images
The optical microscope platform created by UC San Diego bioengineers is one-of-a-kind. It enables the researchers to visually watch, in high resolution, how precise dietary changes impact the way flies convert the energy from their meal into fat.
The gadget also enables the researchers to track the process of converting fat back into energy.
Furthermore, the scientists can now visually monitor the increase in structure in single fat-storage "containers" inside the fruit fly cell type that is equivalent to mammalian fat (adipose) cells.
The researchers exhibited the capacity to visually follow changes in fat (lipid) metabolism in flies after they were fed a variety of different diets in a recent publication published in Aging Cell.
"We can observe where and when fats are being placed into and removed out of storage using our novel optical microscope technology," said Shi, a bioengineering professor at UC San Diego and the paper's corresponding senior author, as per ScienceDaily.
This is the first imaging device that can visualize fat metabolism in individual fat cells at high resolution in both location and time.
We have shown that in response to dietary changes, we can identify where and when lipid metabolism changes inside individual fruit fly fat body cells.
Heavy water, like "normal" water, is freely absorbed into the cells of living organisms.
So, when the researchers give a fruit fly heavy water, the fruit fly starts converting energy from its diet into fat molecules to be stored, part of those fat molecules include deuterium.
The presence of deuterium atoms in lipids contained within the fat cells of fruit flies may thus be used to calculate how much fat the fly has accumulated.
By altering a fly's food at the same time as introducing heavy water, you can track how the diet affects lipid turnover.
The genome of a fly is simpler to analyze than that of a mouse or a human since it just has eight chromosomes.
In comparison, a mouse's genome has 40 chromosomes while a human's genome has 46.
A fly's genome was one of the first to be decoded by scientists, with the job finished by the year 2000. Drosophila has around 15,000 genes that encode protein information.
For instance, humans and mice both have roughly 24,000 genes, a comparison of the human and fly genomes reveals that
Seventy-five percent of the genes known to cause sickness in humans are also found in flies.
Drosophila has more than 90% of the genes that might cause cancer in humans.
Under ideal conditions, a female Drosophila may lay up to 100 eggs every day.
As a result, researchers have a high number of insects available in a short period of time.
Fully developed flies hatch in one to two weeks, depending on the temperature: at 25 degrees, this takes nine to ten days.
During this time, the insects develop into embryos in just one day.
They then go through three larval and one pupal stage before becoming fully-fledged flies. Each year, around 25 generations of flies may be produced in this manner.
In comparison, laboratory mice produce just four to six generations every year.
